1. Field of the Invention
The present invention relates stator core for motor and manufacturing method thereof.
2. Description of the Related Art
Generally, stator core for motor is formed by coiling plural teeth protruded from an inner circumferential surface after a metal core body is configured as a cylindrical shape.
Recently the stator core needs a miniaturization and weight lightening according to a miniaturization of motor, thus a forming the stator core by laminating a thin metal plate with constant thickness or forming the cylindrical shaped stator core by combining a roughly “T” shaped a split core having one teeth is more often used than a conventional forming method using the stator core of one body.
But for the laminating stator core, there is a complication that plural metal plates undergo press working with the same configuration, and then the laminating process should be done separately. Further for the split core, there is a complication that stator core should be formed as a cylindrical shape by a fitting combination for the connecting part of split core using an extra adhesion or arranging a complementary shape due to an air gap in a assembly position for each split core during a combination process of a cylindrical shaped stator core by combination of each split core after each split core is formed by molding or sintering.
Recently for the solution of the described complication, the art which assembles more than one laminated unit core with completion of bending after laminating plural unit core and bending laminated unit core simultaneously, to be ring shaped stator core is stated in the Korean Patent No. 2008-0078944, released on Aug. 29, 2008.
But according to this composition, product defects by the separation of core assembly are mostly likely to occur in a assembly process of stator core after bending, and also there is a problem that if the assembled parts are not firmly fixed, the efficiency for motor can fall or poor performance can occur.